DataSetFilters.select_interior_points

DataSetFilters.select_interior_points(

surface: pv.PolyData,

*,

method: _SelectInteriorPointsOptions = 'signed_distance',

inside_out: bool = False,

check_surface: bool = True,

locator_tolerance: float | None = None,

) → _DataSetType

Mark points from this mesh as inside or outside relative to a closed surface.

Evaluate all of this mesh’s points to determine if they are inside an enclosed surface. The filter produces a boolean point array named 'selected_points' with True values indicating points are inside, and False values indicating points are outside the provided surface.

By default, the input surface is checked to ensure it is closed. Optionally, this check may be disabled.

Note

This filter generates a data array, but does not modify the input dataset. If you wish to extract cells or points, various threshold filters are available (i.e., threshold the output array).

Added in version 0.47.

Parameters:

surfacePolyData

Surface used to test for containment. It should be a closed surface such that it has a defined “inside” and “outside”.

method‘signed_distance’ | ‘cell_locator’, default: ‘signed_distance’

Underlying method used to select points.

• 'signed_distance': Use compute_implicit_distance() and select points based on the distance. Points with negative distance are inside, points with positive distance are outside.

• 'cell_locator': Use vtkSelectEnclosedPoints to select points. This uses vtkStaticCellLocator internally to spatially search for interior points. Use the locator_tolerance to control the search tolerance.

Note

The 'signed_distance' method is generally slower, but is also more reliable for correctly identifying interior points.

Warning

The 'cell_locator' option can erroneously mark outside points as inside.

inside_outbool, default: False

By default, points inside the surface have value True, and points outside have value False. Set inside_out=True to invert this.

check_surfacebool, default: True

Specify whether to check the surface for closure. When True, the algorithm first checks to see if the surface is closed and manifold. If the surface is not closed, a runtime error is raised.

locator_tolerancefloat, default: 0.001

The tolerance on the intersection when using the 'cell_locator' method. The tolerance is expressed as a fraction of the bounding box of the enclosing surface.

Returns:

PolyData

Mesh with a new 'selected_points' point_data array.

See also

compute_implicit_distance, extract_points, extract_cells

Extract Cells Inside Surface

Examples

Determine which points on a plane are inside a manifold sphere surface mesh. Extract these points using the extract_points() filter and then plot them.

>>> import pyvista as pv
>>> sphere = pv.Sphere()
>>> plane = pv.Plane()
>>> selected = plane.select_interior_points(sphere)
>>> pts = plane.extract_points(
...     selected['selected_points'], include_cells=False
... )
>>> pl = pv.Plotter()
>>> _ = pl.add_mesh(sphere, style='wireframe', line_width=3)
>>> _ = pl.add_points(
...     pts, color='r', point_size=15, render_points_as_spheres=True
... )
>>> pl.show()

Static Scene

Interactive Scene

Select the outside points instead.

>>> selected = plane.select_interior_points(sphere, inside_out=True)
>>> pts = plane.extract_points(
...     selected['selected_points'], include_cells=False
... )
>>> pl = pv.Plotter()
>>> _ = pl.add_mesh(sphere, style='wireframe', line_width=3)
>>> _ = pl.add_points(
...     pts, color='r', point_size=15, render_points_as_spheres=True
... )
>>> pl.show()

Static Scene

Interactive Scene